None listed
Conditions
Brief summary
This study is investigating ways to improve treatment of ventricular tachycardia, a potentially malignant heart rhythm disorder, in patients with structural heart disease. Radiofrequency catheter ablation is a recommended approach to treating patients with ventricular tachycardia and structural heart disease, wherein specially engineered wires are passed into the heart where therapeutic lesions can be delivered with heating electrical current. Irrigation fluids, typically 0.9% NaCl saline solution, keeps the catheter cools and reduces risks of blood clots or charring, but also absorbs some of the electrical current that can reduce the the amount of heart tissue treated. An alternative is 0.45% NaCl "half-normal" saline solution, which has been shown to absorb less current, and deliver larger therapeutic lesions. This is a double-blinded, randomised trial to investigate whether using half-normal saline results in better outcomes for patients suffering from ventricular tachycardia.
Interventions
Radiofrequency catheter ablation is a recommended approach to treating patients with ventricular tachycardia and structural heart disease. Catheter hardware is kept cool during the procedure using an irrigation fluid, typically 0.9% NaCl saline solution. Therapeutic current delivered by the catheter can be absorbed by the irrigation fluid. An alternative is 0.45% NaCl "half-normal" saline solution.
The irrigation flow rate (millilitres per min) of both normal saline and half-normal saline to ke
Radiofrequency catheter ablation is a recommended approach to treating patients with ventricular tachycardia and structural heart disease. Catheter hardware is kept cool during the procedure using an irrigation fluid, typically 0.9% NaCl saline solution. Therapeutic current delivered by the catheter can be absorbed by the irrigation fluid. An alternative is 0.45% NaCl "half-normal" saline solution. The irrigation flow rate (millilitres per min) of both normal saline and half-normal saline to keep catheters cool and prevent thrombosis is 2mL/min during diagnostic periods of the procedures and is increased to 8mL/min or 15mL/min during ablation, based on power setting used (e.g., 30 watts, 40 watts). The power is decided based on the operator discretion. As such, the volume of half-normal saline used will be dependent on the duration of the procedure and the amount of time spent delivering radiofrequency ablation. Adherence to the intervention will take the form of operator compliance to the blinding aspect of the study. Intravenous bag covers (typically used to protect light-sensitive products) will be used to conceal the identity of the irrigation to clinical and study personnel who require blinding. Unblinded clinical team members will be limited but will include anaesthetics and nursing staff required to prepare bags saline bags. Unblinding will only take place if clinically required. The intervention in this trial is 0.45% "half-normal" saline, which is routinely available for catheter ablation of ventricular tachycardia in structural heart disease.
Sponsors
Western Sydney Local Health District (WSLHD)
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. >=1 prior episode of sustained VT in the prior 6 months; a. Spontaneous VT: >=1 episode of monomorphic VT treated by anti-tachycardia pacing (ATP) and/or internal shock by an ICD; lasting >=30 seconds in the absence of intra-cardiac device therapy that could either be self-terminating or require reversion by pharmacological therapy or external cardioversion; b. Spontaneous VT: >=1 episode of sustained spontaneous monomorphic VT lasting >=30 seconds documented on Holter, ECG, Loop recorder or other cardiac monitoring device that could either be self-terminating or require reversion by pharmacological therapy or external cardioversion; c. Inducible VT: with syncope or palpitations – inducible VT defined as sustained monomorphic VT of CL >=200 ms lasting for >=10 s during a cardiac electrophysiology study (note with 4 extrastimuli with or without provocation with isoprenaline); 2. Undergoing ventricular tachycardia ablation; 3. underlying structural heart disease; 4. a recipient of an implanted cardiac device such as a pacemaker, defibrillator or a cardiac resynchronisation therapy device and/or is indicated to receive one given a new diagnosis of structural heart disease, based on current guideline recommendations. 5. Aged >=18 years; 6. able to provide informed consent.
Exclusion criteria
1. Unable or unwilling to provide informed consent or patients physician feels there is not significant equipoise to justify randomisation; 2. Women who are pregnant, breast feeding; 3. Medical illness with an anticipated life expectancy <3 months; 4. Unable to complete study procedures or unwilling to be followed up; 5. Have a concomitant illness, physical impairment or mental condition which in the opinion of the study team/ primary care physician could interfere with the conduct of the study including outcome assessments; 6. patient with idiopathic ventricular arrhythmia 7. patient with structurally normal heart 8. known channelopathy such as long QT, short QT, Brugada syndrome, catecholaminergic polymorphic VT
Outcome results
None listed